Install avra by entering the following commands in the terminal:
sudo apt update sudo apt install avra
Description:
assembler for Atmel AVR microcontrollers
Avra is an assembler for the Atmel's family of AVR 8-bit RISC microcontrollers. It is mostly compatible with Atmel's own assembler, but adds new features such as better macro support and additional preprocessor directives.
Homepage: http://avra.sourceforge.net
Version: 1.3.0-3
Section: universe/electronics